This invention relates generally to surgical instruments and more specifically electrosurgical instruments, as well as methods for performing a partial nephrectomy.
A process for recovering the kidney of a patient is commonly referred to as a nephrectomy procedure. When only a portion of the kidney is to be removed, it is referred to as a partial nephrectomy. In this later instance, the procedure is primarily characterized by the nature of the organ itself which is highly vascularized. Cutting into the kidney therefore results in a large volume of blood loss. As a consequence, the partial nephrectomy procedure has been an open procedure which has provided immediate and general access to the organ.
This partial nephrectomy procedure is commonly performed using a scalpel to separate a diseased portion of the kidney from the remainder of the kidney. In order to control bleeding a separate instrument is used to cauterize the incision. The steps of cutting and cauterizing are performed repeatedly until the diseased portion is fully removed from the remainder of the kidney.
Snares are surgical instruments typically including a handle and a snare wire which forms a closed loop with the handle. As the wire is drawn into the handle, the size of the loop decreases and eventually severs any tissue within the loop. This procedure has most commonly been used for small appendages such as polyps that are typically nonvascular. Severing a polyp using a snare there does not create severe bleeding nor any reason to cauterize.
These disadvantages of the apparatus and procedures associated with the related art are overcome with the present invention which comprise an electrosurgical snare. The snare includes an electrosurgical element having a backbone and a plurality of ribs which are formed to control the electrosurgical current density. This element forms at least a portion of the snare loop and provides a capability for electrosurgical cutting as well as cauterizing.
In a method associated with the present invention, the electrosurgical snare is placed over a kidney in proximity T a diseased portion of the kidney. The electrosurgical element is moved into the kidney cutting the diseased portion from the remainder of the organ Importantly, cauterization occurs simultaneously with the cutting step so that the bleeding is immediately controlled in the procedure. The snare is provided with a low profile state to facilitate insertion through a trocar in a laparoscopic procedure.
In one aspect of the invention, an electrosurgical instrument includes a handle having an elongated configuration and extending between a proximal end and a distal end. An electrosurgical assembly extends from the distal end of the handle and forms a continuous loop. The assembly is moveable by operation of the handle between an enlarged state, wherein the continuous loop has a first size, and a contracted state, wherein the continuous loop has a second size smaller than the first size. An electrosurgical element is included in the assembly, the element having an outer surface, an axis, and a lumen extending along the axis. Transverse portions of the electrosurgical element define a plurality of slots extending transverse to the axis and providing fluid communication between the lumen of the electrosurgical element and the outer surface of tile electrosurgical element.
In another aspect, the invention includes an electrosurgical element having an axis and a backbone disposed to extend longitudinally along the axis. A plurality of ribs are included in the electrosurgical element and dispose to extend in a spaced relationship to each other and in a transverse relationship to the backbone. Insulation is disposed to extend along the backbone.
In a method associated with the present invention, the electrosurgical instrument is manufactured by providing a handle having a longitudinal channel. An electrosurgical assembly is provided having a first end and a second end defining a closed loop and moveable within the longitudinal channel of the handle to vary the size of the loop. Slots are created in the electrosurgical element to form a plurality of ribs facing inwardly of the loop and a backbone facing outwardly of the loop. Insulation is placed over at least a portion of the backbone.